Question

1. what happens to a wave during reflection?
2. give one real - world example of reflection.

refraction
refraction occurs when a wave changes speed and bends as it moves from one medium to another.
examples:

• a straw appearing bent in a glass of water
• light bending through a prism or lens

questions

1. what causes a wave to refract?
2. why does a straw look bent when it is placed in water?

diffraction
diffraction occurs when a wave spreads out as it passes through an opening or around an object.
examples:

• sound traveling around a corner
• water waves spreading after passing through a narrow gap

questions

1. what happens to a wave during diffraction?
2. why can you hear someone talking even if you cannot see them around a corner?
3. match each situation to the correct wave behavior.

a. hearing an echo in a canyon→
b. light bending as it enters water→
c. sound spreading through a doorway→
key takeaways

1. which wave behavior involves bouncing?
2. which wave behavior involves bending?
3. which wave behavior involves spreading out?

Explanation:

1. Reflection is the bouncing of a wave off a surface, so the wave rebounds from the boundary, maintaining its frequency but changing direction.
2. A common real-world example is seeing your reflection in a flat mirror, where light waves bounce off the mirror surface to form an image.
3. Refraction is caused by a wave changing its speed as it moves from one medium to another with a different optical density.
4. Light travels slower in water than in air. When light from the straw exits water into air, it refracts (bends), making the straw appear bent at the water's surface.
5. During diffraction, a wave spreads out as it passes through an opening or around an obstacle, rather than traveling in a straight line.
6. Sound waves diffract around the corner: they spread out after passing the obstacle (the corner), allowing the sound to reach your ears even when the source is out of sight.
7. a. An echo is a reflected sound wave, so it matches reflection. b. Light bending when entering water is refraction, as the wave changes speed in a new medium. c. Sound spreading through a doorway is diffraction, as the wave spreads out through an opening.
8. Bouncing of a wave is the defining behavior of reflection.
9. Bending of a wave (due to speed change between media) is refraction.
10. Spreading out of a wave through an opening or around an obstacle is diffraction.

Answer:

1. The wave bounces off a surface, changing direction while keeping its original frequency and wavelength (in the same medium).
2. Seeing your reflection in a flat bathroom mirror.
3. A wave refracts when it changes speed as it moves from one medium to another (with different optical or mechanical density).
4. Light travels slower in water than in air. When light from the straw leaves the water and enters air, it refracts (bends), creating the illusion that the straw is bent.
5. The wave spreads out as it passes through an opening or around an obstacle.
6. Sound waves diffract around the corner: they spread out after passing the obstacle, allowing the sound to reach your ears even when the source is not visible.
7. a. Reflection; b. Refraction; c. Diffraction
8. Reflection
9. Refraction
10. Diffraction